Grinding mill



Feb. 17, 1931.;

R. S. IGLEHART GRINDING MILL Filed Oct. 28, 1929 2 Sheets-Sheet 1 INVENTOR ATTORNEYS R. s. IGLE'HART GRINDING MILL Filed Oct. 28, 1929 2 Sheets-Sheet 2 9, INVENTOR rmwm- ATTORNEYS Patented Feb. 17, 1931 STATESv ATE Q IC ream a rename, or, srmnerrnnn, 01116, ASSIGNOB 'ro THE BAUER nnornnns GOMP AN.Y ,"OF SPRINGFIELD,YOHIO, A CORPORATION OF" OHIO GRINDINGQMILL Application filed ()ctober as, 1929.; Serial No. 402,891.

" p ,T is vremain has to'grinding' lit relating more particularly to mills wh1ch employ a rotary grinding element which cooperateswith'a stationary grinding'elcment supported .by thecasing of thermill and in which the direction-of rotation of the rotary grinding element may be'reversed. One of the special features to which the invention relates is the-provisionof means for reversrection of rotation to adapt the mill to dif-' ing the position of-the stationary grinding.

element with relation to the rotary grinding element as well as the feeding and discharge devices tor-correspond with the desired d1- adapted to the installation desired.

One of the objects of this invention is to so construct the mill that the relation of such parts as the grinding elements and the feeding and discharge devices may be readily altered at the place of installation so that the mill may be assembled in a uniform manner at the factory in a way suitable for a ma ority ofinstallations, but be readily alteredatth'e place of installation. tovadapt the mill to a desired installation.

'-Another object of the'invention is to improve' the constructionof the discharge device so. that these devices may not only be adjusted to the desired installation but alsoso constructed and so adjusted with relation to the grindin mechanism as to secure the most eflicient scha'rge of difierentkinds of ground material.

i In the accompanying drawings Fig. l is an end elevation of,-in the pres-' ent case, a hammer'mill in which are incorporated the improvements tolbe described; =3way the upper casing-is positioned. The 100 I Fig. 2 is a fragmentary end elevation of the same machine, the machine having been converted for the opposite direction of rotation.

Fig. 3is a fragmentary end elevation of a portion of a main side rams.

Fig. 5 is an elevation of a detail.

Fig; 6 is an elevation, partly in section of a detail.

Referring to the dra'wings,.in the present case the rotary grinding element is shown in the form of hammers 1 pivotally mounted on rods 2 which are secured to disks 3, the disks being spaced apart to rovide for the usual loose mounting of the iammer; the disks 3 being keyed to a shaft 4 which is rotatably mountedin bearings'5 secured to end plates 6 which constitute the main frame of the machine. A 'reversible electric motor M is shown in direct connection with the shaft 4.

The end plates are secured one to another at the proper distance apart b front and rear plates 7 and 8, preferably y welding; the end plate 6 and plates 7 and 8 forming a lower stationary rectangular casing open at the top and bottom. a

Cooperating with the rotary grinding element is a stationary grinding element in the form of a curved breaker plate 9, whose lowermost edge terminates near the horizontal 7 center line and in close proximity to the ends of the hammer when extended radially. The breaker plate is secured within an upper movable casing, open at one side and the bottom, this movable casing being formed of plates lO which form the ends and a curved plate llwhich forms one side and the top. This movable casing is arranged to be hingedly mounted on either side. of the lower casing and to that endthe lower casing has ears 12 secured to both upper corners of each end plate 6, the ears of each end'plate being arranged at equal distances from theverticalcenter line of the mill. These ears carry rods l2' and the lower corner; of each end Fig. 4 is a front elevation of the machine.

plate 10 of theupper casing, adjacent the open side thereof ils perforated to receive ei ther end of the rods. depending upon which closed side of the upper casing is providedwith a suitable latch L to engage with the adjacent rod 12' to hold the upper casing in closed position. The upper casin carries a feed trough 13 which projects intb the open side thereof, the inner end of this trough being supported by a rod 13' supported y the end walls 10 and the outer end of the trough being supported by pivoted links 13".

As the grmdmg of the material is accomplished by the 'proner co-action of the hammers and the breaker plate, it will be seen that the breaker plate must be positioned in accordance with the direction of rotation of the hammers and that the feed trough must be likewise so positioned. The usual method of assembly of the parts is illustrated in Fig. 1. If, however, the installation must be such that the material should be fed from the oposite side of the machine, the upper casing is reversed by hinging it to the rod 12' on the left hand side of the machine as shown in Fig. 2 which changes the location of the breaker plate with respect to the hammers and also to the location of the feed trough; the direction of rotation of the hammers being reversed by suitable changes in the motor m a well known manner. It should be stated that the upper casing is hinged to the lower casing for the purpose of permitting access to the interior of the mill when desired.

The ground material is conveniently removed from the machine and conveyed to a suitable point of storage (not shown) by means of an air current set up by a fan 14 which is, in the present case, secured to the outer end of the shaft 4. The fan casing 15, Fig. 6, is a simple element, composed of sheet metal ends 16 and a connecting sheet metal member 17 curved to a volute-like form and further provided with a bolting flange 18 b which it is attached to the flange of a disc arge conduit 18'. By reason of similar bolt spaclng in each of the ends 16 itis possible to transpose the fan casing so that'the placement of the fan casing is in accordance with the rotation direction of the fan, as will be noted in Fi s. 1 and 2. The fan casing is bolted to a at metal disk 19, which is bolted to a bracket 20, this bracket in turn'being secured to one of the end members 6. The fan 14 has a series of radial vanes 21 which establish an ample air flow regardless of the rotation direction.

The openings 22 in each end plate of the fan casing 15 provide for influx of material to the fan, the ground material being conveyed from the space 23 in the lower portion of the machine below the hammers to the fan by a curved duct 24. This duct 24 is of circular cross-sectional form at the point of its connection at the fan casing, and changes to an approximate ellipsoidal format its connection with the hammer housing for the purpose of providing that a large amount of ground material may be removed readily rom the space 23. It will be noticed in Figs. 1 and 2, that the long axis of the ellipsoidal --end of the duct 24 is approximately concentrically disposed with reference to the semicircularly curved perforated screen plate 25 which serves to merely determine the degree of coarseness to which the material is to be ground. Most of the air passing through the fan must ass through the screen 25, carrying the bro en particles with it, and in order to realize a high capacity factor, it is essential that the screen be kept constantly cleared of meal or ground material, this being insured by a duct havin an elongated opening approximately concentric with the screen. As a further advantage tending towards ready removal of meal, the form of the duct changes from ellipsoidal to circular in a gradual manner and it has been found that this shape of duct permits the use of a radial blade fan of the kind described which operates in either direction, thus avoiding the necessity of employing a fan having tangential vanes which would have to be reversed if the direction of rotation was reversed.

Inasmuch as the size of the perforations of the screen 25 determine the coarseness of the ground product, it follows that some materials after contact with the rapidly revolving hammers and the breaker plate will be broken sufiiciently to pass through the screen at a point near the upper end thereof, and in order to prevent clogging the chamber 23 at the'point indicated by the character 26 which may occur in coarse grinding the duct 24 is shifted as shown in Fig. 1. In this position the duct presents an end of its ellipsoidal opening nearer the point of possible clogging and thus maintains a strong draft of air through theadvaneed portion of the screen. This has a double beneficial effect as clogging of the screen result-sin lowered capacity andfurther breaks the material to an undesired fineness by reason of the extended contact with the hammers.

The duct is bolted to the fan casing by bolts 27 passing through cars 28 on the end i of the duct which have elongated openings. At its lower end it is secured by bolts passing through the cars 28 and interposed between the duct and the end plate 6 is an adapter plate 29, Fig. 5, which is provided with bolt holes 30, corresponding to screw holes 31 n end plate 6 (see Fig. 3). The opening 32 1n the plate 29 is at one side of the center of the plate so that if the meal is to be withdrawn at an early period in the grinding stage the plate 29 is placed on the end plate 6 as in Fig. 1, and the duct shifted and secured to the plate 29. If a finer screen is employed, it may be advantageous to shift the discharge opening,

., is indicated by which case the plate 29 is reversed to have the opening 32 in alignment with the right hand 7 portion of the symmetrical opening 33 in the mill-may be readily sembly by of rotatin end plate 6. The chamber 23 beneath the screen 25 is enclosed by steel sheet wall 23" which acts to properly convey the ground material to the discharge opening 33.

By this construction it will be seen that the re-assembled and adjusted tomeet conditions of installation other than those contemplated by the original assimply reversing the upper half of the casing onv the lower half, reversing the fan casing and adjusting the discharge duct. in the event that the duct has been originally assembled for a certain material. As explained in the specification the dischar e duct may be positioned with relation to t e discharge opening fromthe casing to, meet the conditions ofdifi'erent kinds of material, so that the purpose therefore of adjustably coppecting the duct with the casing is twofo 1 Having thus described my invention, I claim:

1. In a grinding mill, a grinding element capable of rotation in either direction, a nonrotatable grinding element, a feeding device,

'common means for supporting said non-rotatable ind-ing element and feeding device, means or supporting said common means such that the position thereof may be reversed, whereby the non-rotatable grinding element and the feeding device ma each be positioned on either side of the depending on the direction of rotation of said rotatable grinding element, a fan casing connect-, 'ed with the mill, a fan in'said casing capable in either direction with said rotatable grinding element, said fan casing. having an ofiset discharge opening and being reversible to alter the position .of said discharge opening to conform with the direction of rotation of said fan. v.

2. In a inding mill, a casing formed of a lower stationary member and an upper movable member, a rotary horizontal shaft carried by said lower casing member capable of rotation in either direction, a grinding element carried by said shaft, a grinding plate mounted at one side of said upper casing member and means for removably connecting said casing memberstogether whereby the upper casing member may be assembled with said grinding plate on either end or the outer sides-of the vertical center line of said rotary grinding member, a fan connectedwith said shaft on the outside of said casing, a'fan'icasing' fonsaidshaft having an offset and means forso supdischarge opening of an charge opening of said porting said -fan casing that the position thereof may be reversed.

3. In a' grinding mill,a casingrformed of a lower stationary member and an upper movable member, a rotatable horizontalshaft carried by the lower member capable. of rotation in either direction, agrinding plate carried at one side of said upper casing member, andmeans for 'removably connecting the two casing members together whereby the upper casing member may be reversed to position the grinding plate and the feed.

chute each on either one side or the other of the vertical center line of saidrotary grindingmember, a fan having radial blades connected with said shafton'the outside of said casing, a fan casing for saidfan having anofl'set dlscharge opemng, and means for ref versing the 4. In a tar of.

position of said fan casing.

grinding mill, a main casing, a regrinding element in said casing capable aving its direction of rotation reversed,

a fan on the outside of said main casing, a fan casing for said fan having an offset discharge opemng, each side of said fan casing having an inlet opening, a chute leadin'g'from said main casing to said fan casing adapted to be connected with either side thereof, and means for supporting said fan casing suchtthat the position thereof may be reversed.

5. Ina tary grinding element in said casing capable of having a fan on the outside of said main casing, a fan casing for said fan" havin an ofi'set dis charge opening, each side 0 said fan casing having an inlet .opening,;a chute leading Y from said main casing to said fan casing adapted to be connected with either side thereoflmeans for supporting said fan casing such that the position thereof may be reversed, and means for adjustably connecting said chute to both the main casin I and fan casing whereby-the inlet end 0 chute may be positioned at different points with relation to said main casing.

6. In a grinding ing elements therein, acurved grate Sifldl grinding elements,

low

elongated character, a fan casing, a chute connecting said casings, the inlet end of said chute bein gated character of less area than the dismain casing, and a reversible adapter plate servin to connect the inlet end of said chute wi said main its direction of rotation reversed,

' said.

said casing having a grinding mill, a main casing, a ro-' mill,amain.casing, indof an eloncasing having an opening corresponding to the area of the inlet openingof said chute.

mill, 8. main casing, dis-,

. 7; In a grinding integrating elements in said casing, a curved grate beneathsaid disinte atin elements, a fan casing, a chute lea g om a discharge opening in said main casing below said grate to said fan casin the discharge opening of saidmain casingbeingof greater width than the inlet of said chute, means for connecting the inlet end of said chute to the main casing at one point 'or another in the direction of the Width of said discharge opening, and means for closing that part of said discharge opening not in registration with the inlet end of said chute.

' 8. In a grinding mill, a main casing, rotatable disintegrating elements in said casing, a grate formed on the arc of a circle concentric with the axis of rotation of said disintegrating elements, a fan casing, a chute leading from a discharge opening in said main casin below said grate to said fan casing, the inlet opening of said chute being of an elongated character in the direction of its Width and said discharge opening being of greater width than the width of said chute inlet, means for connecting the inlet end of said chute to the main casing at one point or another in the direction of the widthv of said discharge opening, means for adjustably connecting the discharge end of said chute to said fan casing at a point such that the movement of the inlet end of said chute in altering its point of connection with said casing will be such as to be substantially concentric to said grate, and means for closing that part of said discharge opening not in registration with the chute inlet.

In testimony whereof, I have hereunto set my hand this 22nd day of October, 1929.

. RICHARD S. IGLEHART. 

